Blog Article
Surface texture measurement – Ra, Rz, Rmax, Rz1max, Maximum Height
June 22, 2020This article discusses several key surface texture measurement parameters: average roughness (Ra), average maximum surface height (Rz), maximum of all per-sampling-length peak-to-valley heights (RMax), and the Maximum Height (Rz1max). We
Surface finish for medical devices
June 14, 2020Artificial medical devices prolong life and preserve quality of living. To design devices that will function reliably and safely for decades requires careful attention to materials and surface finish. Accurately
Parameters Primer: Stylus(X,Y) Parameters
May 12, 2020The Stylus (X, Y) parameters (Rk, Rpk and Rvk) are derived from the Bearing Area Curve, based on the ISO 13565-2:1996 standard. The Bearing Area Curve, (also called the Bearing Ratio Curve, or
Nanometer-scale roughness
April 11, 2020“Nanometer-scale” surface roughness may seem rare and specialized. But, in fact, many components and common products require nanometer-scale, or sub-nanometer-scale, average roughness (Sa) in order to function properly. The ability to
How many measurements?
March 3, 2020Multiple surface texture measurements made in different locations over a surface will generally demonstrate some variation in the texture parameter being assessed, such as average roughness (Ra) or peak-to-valley height
What wear measurement may and may not show you
March 10, 2019One of the great challenges of product design is accurately assessing how a component will wear in order to maximize its useful lifetime. Wear is, of course, caused by a
Parameter Primer: Sds (Summit Density)
February 9, 2019Sds, the Summit Density, is one of the so-called “Hybrid” surface texture parameters. Sds counts the number of summits per unit area of the surface. The summits are derived from
Surface texture measurement – did you set the cutoff lengths properly?
January 21, 2019Along with specifying the surface roughness with Ra (average roughness), one must establish the cutoff lengths used to measure the surface. A specification of Ra alone is inadequate, since measurement
Take a hike! Understanding form, waviness and roughness in terms of a good walk
January 8, 2019The terms “roughness,” “waviness” and “form” are used everywhere in discussions of surface texture. But do we really understand how they are defined? For many years I have used an
If you need less sliding friction, should you make the surface rougher or smoother?
July 6, 2018How is sliding friction affected by the surface texture of two dry parallel sliding surfaces? The relationship of dry (sliding) friction to surface texture is linked to the notion of